Revert "Move more internal methods from GrContext to GrContextPriv"

This reverts commit f440cecbfdf1910104f36aedd0e963da2ae8b6a8.

Reason for revert: breaking android builds. 

Original change's description:
> Move more internal methods from GrContext to GrContextPriv
> 
> TBR=bsalomon@google.com
> Change-Id: Ia8cf0e0d30451c69bc7a08215aafa6abe6e0ddbe
> Reviewed-on: https://skia-review.googlesource.com/97080
> Commit-Queue: Robert Phillips <robertphillips@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>

TBR=egdaniel@google.com,bsalomon@google.com,robertphillips@google.com

Change-Id: If263f8161f0fbe3fc6ee8f34bb09e237705c3694
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/97200
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
diff --git a/tests/ImageTest.cpp b/tests/ImageTest.cpp
index 83ff47c..078bd7c 100644
--- a/tests/ImageTest.cpp
+++ b/tests/ImageTest.cpp
@@ -723,9 +723,8 @@
     std::unique_ptr<uint32_t[]> pixels(new uint32_t[kWidth * kHeight]);
 
     GrContext* ctx = ctxInfo.grContext();
-    GrGpu* gpu = ctx->contextPriv().getGpu();
 
-    GrBackendTexture backendTex = gpu->createTestingOnlyBackendTexture(
+    GrBackendTexture backendTex = ctxInfo.grContext()->getGpu()->createTestingOnlyBackendTexture(
                pixels.get(), kWidth, kHeight, kRGBA_8888_GrPixelConfig, true, GrMipMapped::kNo);
 
     TextureReleaseChecker releaseChecker;
@@ -757,7 +756,7 @@
     refImg.reset(nullptr); // force a release of the image
     REPORTER_ASSERT(reporter, 1 == releaseChecker.fReleaseCount);
 
-    gpu->deleteTestingOnlyBackendTexture(&backendTex);
+    ctxInfo.grContext()->getGpu()->deleteTestingOnlyBackendTexture(&backendTex);
 }
 
 static void test_cross_context_image(skiatest::Reporter* reporter, const GrContextOptions& options,